Patterns of Inheritance Flashcards
_____________ means identical alleles at a genetic locus
homozygous
___________ means two different alleles at a genetic locus
heterozygous
________ ______________ two different alleles at two different genetic loci (base pairs) in the same gene
compound heterozygote
___________ ____________ means two different alleles at two different genetic loci in different genes
Double heterozygote
____________ is the proportion of individuals with a gene mutation who actually express the disease condition. The probability that a genetic variation (or allele) will yield the phenotype at all.
penetrance
___________ ___________ is the phenomenon of differing clinical features (phenotype) among individuals carrying the same genotype
variable expressivity
____________ effect—high frequency of a gene mutation in a population founded by a small ancestral group
founder effect
(bottle neck effect)
Two most common mutations in Tay sachs in the ____________ gene on chromosome 15
TATC (80%) insertion in exon 11
intron 12 splice site alteration
G269Ser in exon 7
What are Mendel’s 3 laws?
- Law of segregation
- Law of independent assortment
- Law of dominance
Mendelian disorders are ________-gene disorders
single
Chromosomal disorders are less often _________ and usually syndromic
inherited
In autosomal dominant inheritance the dominant gene is located on an _______________ and each child of an affected parent has a __% risk
autosome
50% risk
In autosomal dominant inheritance males and females are affected _____________ and the inheritance pattern is __________ with male to male and female to female inheritance observed
equally
vertical
In _____________ ______________ the phenotype of heterozygous is intermediate between heterozygous and homozygous
incomplete dominance
In co-dominance the contributions of both alleles are visible in the ____________
phenotype
Type of inheritance
AD
Disease and inheritance?
- MVP, aorta dilitation, tall - arachnodactyly, scoliosis, lens dislocation and myopia
Marfans -FBN1 gene chromosome 15
autosomal dominant
_________ criteria for diagnosing Marfan syndrome
Ghent
Inheritance pattern?
AR
In autosomal recessive disorders the carrier parents have a _______% chance of having an affected child. Females and males are affected equally. If both parents affected then _____% offspring are affected
25%
100%
In autosomal recessive enzymatic diseases the phenotype can be the result of precursor __________ or the ___________ of product
accumulation
absence
Type of inheritance?
XR
In ________ -_________ ___________ inheritance affected individuals are primarily male with unaffected parents. All female siblings will be carriers and the male offspring of the proband are affected
X-linked recessive